Abstract
A genetic variant may alter a gene expression level and as a result be associated with pathological characteristics in breast cancer. In this research, the frequency and association of the ErbB4 3'-untranslated region (3'-UTR) variant, rs12471583 (c.*3622A>G) was studied in an Iranian breast cancer patients. In silico assessment was performed to predict the function of the rs12471583 variant located on the 3'-UTR of ErbB4. Furthermore, as a case-control study, this polymorphism was genotyped in 243 breast cancer patients and non-cancerous controls using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. The Armitage's trend test and regular association tests were performed to analyze a possible association between the rs12471583 and risk of breast cancer and its relevant pathological traits. The bioinformatics analysis predicted that the rs12471583 SNP is located on the four miRNA binding sites, including miR-511-5p, miR-4659a-5p, miR-4659b-5p, and miR-6830-3p. According to logistic regression tests, the G allele is negatively associated with ER- (OR = 0.20, 95% C.I. = 0.04-0.93, p = 0.026), PR- (OR = 0.31, 95% C.I. = 0.10-0.98, p = 0.039), ER-/PR- (OR = 0.20, 95% C.I. = 0.04-0.93, p = 0.026), and advanced breast cancer (OR = 0.40, 95% C.I. = 0.18-0.85, p = 0.016). It has been found that ErbB4 expression may be linked to unfavorable outcomes in breast cancer. Likewise, our results suggest that the G allele may strengthen miRNA-ErbB4 binding efficiency and as a result reduce expression of ErbB4. This is a possible explanation for the observed association.